The present invention relates to an image processing system, a projector, a program, an information storage medium, and an image processing method that correct color non-uniformity in images.
When an image is displayed for a long time by an image display device such as a projector, color non-uniformity (including color non-uniformity due to luminance non-uniformity) is created in the image and thus the image gradually deteriorates.
This could happen when a projector is used to display an image continuously on a screen in a store or exhibition hall, for example. In such a case, the original display effect could be lost due to deterioration of components such as the liquid-crystal panel or a polarized plate during projection over a long period of time, which could generate color non-uniformity in the image.
As an example of a solution that addresses the above problem, Japanese Patent Application No. 2000-334149 (Japanese Patent Application Laid-Open No. 2002-140060) discloses an image display system having a bulletin means that measures the operating time of a display means and correction means that corrects information for image modification in such a manner that a target color is reproduced, based on the time information and target color region information, in order to automatically correct deterioration of a uniform color due to deterioration caused by a light source or the like.
However, color non-uniformity deterioration does not include only deterioration of the entire image; it also includes deterioration of parts of the image.
With a liquid-crystal projector, by way of example, long-term use can lead to variations in the quantity of light in components such as liquid-crystal light valves and polarized plates, caused by the effects of light from light sources. Variations in light quantity are particularly likely to occur in liquid-crystal light valves and polarized plates within the paths of powerful blue light and highly energy-intensive (large light quantity) green light. Such deterioration in the liquid-crystal light valves or polarized plates leads not only to deterioration the entire polarized plates, but also to deterioration of parts thereof. As a result, not only the entire image, but also parts of that image could deteriorate.
In such a case, it would be difficult to correct the image as appropriate with the method disclosed in Japanese Patent Application Laid-Open No. 2002-140060, wherein information on the operating time of the display means.